Anybody have a story of a mechanical head not opening, either in a target or while shooting at an animal? Just curious because my hunting buddy had one not open in his broadhead target a couple of days ago. 3 new heads and two opened just fine while one never opened on a shot. This shook his confidence and he is going to use his Thunderheads in Colorado. Not trying to start any war, just wondering if anyone has any story to share about a mech head not opening. By the way, the head was a NAP Shockwave.